In mining and construction/demolition applications, a problem may arise when unstable material is caught in a suspended location. Efforts to release the material from the suspended location can be difficult, and place workers in a hazardous situation.
Block cave mining is a particular type of mining where ore is broken and directed to fall through vertical passages (drawbells), for collection and processing. It is fairly routine in block cave mining for the broken ore to become trapped in the drawbells in a suspended location. Accordingly miners in block cave mining are regularly faced with the problem for resolving roof falls.
The present application is described in terms of block cave mining as a suitable application, however it is understand that the systems and methods described within are applicable to other applications that require resolving unstable material caught in a suspended location.
In the field of block cave mining, several methods have been used for resolving material caught in a suspended location. These methods include: (a) manual methods inserting explosives, (b) mechanical prying techniques and (c) launching mortar rounds. Each of these methods involves significant risks and limited success. In particular, the manual methods typically require a worker to be located in an unsafe location near, i.e. above or below, the suspended material. Sudden release of the material placing the workers at physical risk. The remote method of launching mortar rounds brings a number of risks to bear, and requires a relatively large amount of explosives since the round impacts the surface of the material.
There is a need for an improved system and method for resolving material caught in suspended locations, including “hang-ups” occurring in block cave mining.